The present invention relates to thermal insulating panels, and more particularly to thermal insulating panels applied to metal ductwork.
Prior to the present invention, thermal insulation has long been applied to ductwork to minimize heat transfer from such ductwork to the atmosphere and vice versa. When cooling air flows through such ductwork, it is important that losses to the atmosphere be minimized, and under heating conditions it is equally important that heat losses to the atmosphere be minimized. Currently various insulation are used and field applied. These applications consistently fail. Such approaches are short term at best, and before long the insulation often falls away from the ductwork thereby exposing at least part of the ductwork to the atmosphere.
When used outside, it is extremely important that duct insulation insure a weather tight seal. However, in the insulating systems used heretofore this objective was not achieved. Also, in the past, insulating systems have failed to provide a thermal, weatherproof, antibacterial system for outside ductwork.
Accordingly, it is an object of the present invention to provide thermal insulating panels particularly constructed for application to ductwork for insulating the ductwork in a highly efficient and dependable manner.
Another object of the present invention is the provision of thermal insulating panels which are simple in construction but easy to use in the insulation of ductwork in both inside and outside installations.
Still another object of the present invention is a system of thermal insulating panels that interconnect and interlock with one another in a highly efficient and dependable manner to provide a thermal, waterproof, antibacterial system.
Another object of the present invention is a plurality of interlocking thermal insulating panels that provide a weather tight seal when assembled on the outside of rectangular ductwork.
In accordance with the present invention, thermal insulating panels for application to HVAC rectangular ductwork comprise a first layer of solid insulation, a second layer of solid insulation laminated to the first layer, and an outer metal layer laminated to the second layer. The first and second layers may be made from polyisocyanurate insulation, and collectively they have a insulation value of at least R-14. The outer metal layer preferably comprises embossed aluminum.
An insulated ductwork comprises a rectangle duct with four corners, and at least four interlocking insulating panels, one on each side of the rectangular duct joined together at the four corners of the duct. The outer embossed aluminum layer of at least some of the panels in this four panel arrangement includes right angle flanges along the panel sides thereof for attachment to an adjacent panel in that arrangement. Each side of the rectangular duct may include a plurality of thermal insulating panels arranged end-to-end in a series along each side of the rectangular duct. Adjacent panels in the series are joined together in overlapping relationship with one another.
The rectangular duct may include a plurality of sections arranged end-to-end in a series with outwardly extending peripheral flanges on each duct section at the ends thereof. The peripheral flanges of adjacent duct sections are connected together, and the first layer of solid insulation of each insulating panel may include cut-out portions to accommodate the interconnected flanges of the duct sections.